 |
 |
 |
|
| home | CME | help | feedback | subscriptions | archive |
|
The Journal of Bone and Joint Surgery (American). 2008;90:1348-1360. doi:10.2106/JBJS.G.01241 © 2008 The Journal of Bone and Joint Surgery, Inc.
Management of Chronic Ruptures of the Achilles Tendon
1 Department of Trauma and Orthopaedic Surgery, Keele University School of Medicine, Thornburrow Drive, Hartshill, Stoke on Trent ST4 7QB Staffs, England. E-mail address: n.maffulli{at}keele.ac.uk
Disclosure: The authors did not receive any outside funding or grants in support of their research for or preparation of this work. Neither they nor a member of their immediate families received payments or other benefits or a commitment or agreement to provide such benefits from a commercial entity. No commercial entity paid or directed, or agreed to pay or direct, any benefits to any research fund, foundation, division, center, clinical practice, or other charitable or nonprofit organization with which the authors, or a member of their immediate families, are affiliated or associated.
Chronic ruptures of Achilles tendons are those that present four to six weeks after the original injury. They have become more common as acute Achilles tendon injuries have become more frequent, and they are associated with considerable functional morbidity. Most surgeons agree that chronic ruptures should be managed operatively. Diagnosis is based predominantly on history and clinical examination. Real-time, high-resolution ultrasound and magnetic resonance imaging are helpful in preoperative planning or as a diagnostic aid. Local tissue, local tendons, and allografts can be used to reconstruct the tendon, and end-to-end repair is possible if the gap is <2.5 cm. Compared with acute injuries, chronic injuries are associated with a higher rate of postoperative infection and more prolonged recovery.
Ruptures of the Achilles tendon are especially common in middle-aged men who occasionally participate in sports1-4. In some cases, a patient sustains a rupture, but this is not diagnosed and the patient presents with a chronic rupture four to six weeks later5-10. Although there is still much controversy about how to manage acute ruptures, most surgeons agree that chronic ruptures should be treated operatively when possible, as they are associated with considerable functional morbidity. An ankle-foot orthosis can be used to manage a chronic rupture in a low-demand individual or in a patient in whom operative management is contraindicated.
A chronic rupture of the Achilles tendon causes difficulty with and impairment of ankle plantar flexion11. The tendon sheath often becomes thickened and adherent to the retracted ends of the tendon, and there is minimal repair tissue in the gap11-13. The proximal stump is often conical14 and adherent to the fascia posterior to the flexor hallucis longus muscle belly12. The distal stump often looks bulbous. If the plantaris tendon is present, it may be hypertrophied. Thickened scar tissue commonly bridges the rupture site13,15-17 in an attempt at repair18. A well-organized connective tissue repair response was seen fifty-six days after resection of calcaneal tendons in rabbits, but a fascicular arrangement of collagen fibers typical of a tendon was still not present by 240 days19. The repair tissue is not as strong as intact tendon, and it elongates with time13,20. Retraction of the proximal stump results in shortening of the intact proximal gastrocnemius-soleus complex. This reduces its biomechanical efficiency and the contractile force that the muscle can develop. The overall effect is weakness of ankle plantar flexion and hence a flat-footed, nonpropulsive gait on the affected side.
Chronic Achilles tendon ruptures normally present as a result of a misdiagnosed, neglected, or unrecognized acute rupture. Patients may describe a sudden sharp pain in the calf, as if kicked from behind21, while they were engaged in sports activity. Alternatively, they may recall a minor injury with an initial episode of heel pain. Subsequently, routine daily tasks such as walking uphill or climbing stairs become difficult3. Diagnosing an acutely ruptured Achilles tendon is usually straightforward if the history and findings on examination are clear. Nevertheless, as much as a fifth of these lesions can be missed22. In one study, nine (36%) of twenty-five elderly patients had a delay of more than one week before treatment because the condition was not diagnosed at the time of injury23. When a patient has a chronic rupture, the pain and swelling have often subsided and the gap between the tendon ends has filled in with fibrous tissue23-25 (Fig. 1). In addition, active plantar flexion, although weak, may be possible through the action of the tibialis posterior, flexor hallucis longus, flexor digitorum longus, and peroneal muscles. These residual functions may make it difficult to confirm the correct diagnosis through clinical examination alone26. A limp is often present27. A high index of suspicion is needed, and a range of special tests and investigations can aid in accurate diagnosis.
Clinical Examination On inspection, there may be a visible gap at the rupture site. The calf muscles may be wasted. The long toe flexors may accommodate for the lack of function of the gastrocnemius-soleus complex, producing clawing of the toes and an apparently higher medial arch of the foot. The clinical tests described here have been systematically studied for the diagnosis of acute ruptures; their applicability to chronic cases has, to our knowledge, not been investigated. The calf squeeze test, also known as the Thompson test, was first described by Simmonds in 195728. The patient lies prone on the examination table with both feet over the edge. The calf is squeezed and, if the Achilles tendon is intact, the foot will plantar flex as the tendon connects the gastrocnemius-soleus complex to the calcaneus. When the tendon is torn, and thus no longer connects the gastrocnemius-soleus complex to the calcaneus, the foot will not plantar flex as much as it does on the normal side. The Matles test29 is also performed with the patient lying prone. The knees are flexed to 90°. The ankle on the ruptured side will assume a more dorsiflexed position as compared with the normal side. This is due to the absence of normal tension under which the tendon connects the gastrocnemius-soleus complex to the calcaneus and hence the effects of gravity make the foot dorsiflex more on the injured side. With the O'Brien needle test30, also done with the patient prone, a hypodermic needle is inserted off the midline 10 cm proximal to the calcaneal insertion of the Achilles tendon, such that its tip lies within the substance of the tendon. The ankle is then manually plantar flexed and dorsiflexed by the examiner. If, on dorsiflexion, the pin moves so that it points proximally, the area of tendon between the pin and calcaneus is presumed to be intact; if not, then a rupture is probable. Copeland described a test performed with a sphygmomanometer31. A sphygmomanometer cuff is wrapped around the midpart of the calf with the patient lying prone. The cuff is inflated to 100 mm Hg (13.3 kPa) with the foot in plantar flexion. The foot is then dorsiflexed by the examiner. If the pressure rises to approximately 140 mm Hg (18.7 kPa), the musculotendinous unit is presumed to be intact. If the pressure on dorsiflexion remains approximately the same, a rupture is presumed. If two of the tests described above are positive, a diagnosis of a ruptured Achilles tendon is certain24.
Imaging Real-time, high-resolution ultrasonography is inexpensive, rapid, and dynamic33. However, it is highly user-dependent, requiring training and experience to correctly interpret the images. A linear-array transducer probe is held perpendicular to the skin overlying the tendon. Ultrasound gel is used to ensure that the optimal amount of energy is returned to the transducer probe, enabling good dynamic and panoramic images of the tendon34,35. The longitudinal collagen fibers in the Achilles tendon reflect ultrasonic energy, and high-frequency probes show the tendon best36. A normal tendon appears as a hypoechogenic, ribbon-like image contained between two hyperechogenic bands. These bands are separated when the tendon is relaxed and are more compact when the tendon is under tension. When the Achilles tendon is ruptured, ultrasonography shows tendon discontinuity with decreased or increased echogenicity, depending on the chronicity of the rupture37 (Fig. 2).
Magnetic resonance imaging can show in detail the condition of the ends of completely ruptured tendons38. A normal Achilles tendon is viewed as an area of low signal intensity on all sequences. It tapers smoothly with no focal defects. The dark band of the tendon itself can be distinguished from the high signal intensity of the pre-Achilles fat pad38. Chronic ruptures are seen as an area of low signal intensity on T1-weighted images and as discontinuity and altered signal on T2-weighted scans. The condition is best appreciated on sagittal views (Fig. 3).
Management of chronic Achilles tendon ruptures is challenging. The ends of the tendon are frequently retracted and have an atrophic appearance.
Conservative Management A brace or ankle-foot orthosis can be beneficial for patients who undergo conservative management13.
Operative Management In Myerson's classification13, a Type-1 defect is no more than 1 to 2 cm long. It is managed with end-to-end repair and a posterior compartment fasciotomy. A Type-2 defect ranges between 2 and 5 cm. It is managed with V-Y lengthening, with or without a tendon transfer. A Type-3 defect is >5 cm and is bridged with use of a tendon transfer, alone or in combination with a V-Y advancement. In Kuwada's classification40, a Type-I lesion is a partial rupture and is managed with plaster cast immobilization. A Type-II lesion is a complete rupture with a defect of up to 3 cm in length. It is managed with end-to-end repair. A Type-III lesion is a complete rupture with a defect of 3 to 6 cm after débridement of the tendon ends to healthy tissue. It is managed with a tendon graft, with or without augmentation with a synthetic graft. Finally, a Type-IV lesion is a complete rupture with a defect of >6 cm in length after débridement of the ends of the tendon to healthy tissue. A gastrocnemius recession, a free tendon graft, and/or a synthetic tendon graft are used for this type of lesion.
V-Y Tendon Alignment Leitner et al.42 reported good results in three patients in whom a tendon defect of 9 to 10 cm had been managed with this technique. Kissel et al.43 used this technique, with augmentation with the plantaris tendon and a pullout suture, successfully in fourteen patients. Parker and Repinecz44 described a similar procedure (a modified Strayer gastrocnemius recession) whereby a tongue-in-groove advancement of the gastrocnemius aponeurosis was used to close a 6.5-cm defect in one patient. They reported this to be technically easier than a V-Y advancement and claimed that 50% more length could be achieved. None of these studies were well designed or well conducted, and none involved a sufficiently large number of patients to allow us to draw useful conclusions.
Turndown Flaps Silfverskiöld45 described a similar procedure, but he rotated the flap 180° so that the smooth tendon surface stayed superficial. Modifying this further, Arner et al.15 used two flaps, one medial and the other lateral, and rotated both, in opposite directions. Gerdes et al.46 showed, in a cadaver study, that flap-augmented repairs had a 41% higher tensile strength than end-to-end repairs alone (217.5 ± 44.7 N compared with 153.9 ± 30.2 N). Rush17 used the aponeurosis of the gastrocnemius-soleus muscle complex fashioned into a tube to reconstruct an Achilles tendon with a neglected rupture. Five patients had a good result with this technique. Bosworth20 showed, in a group of seven patients, that a strip of the superficial part of the proximal Achilles tendon stump can be used to augment the repair. A strip of proximal tendon on a distal pedicle is threaded through the trimmed ends of the ruptured tendon and sutured to them. No complications were reported after an average duration of follow-up of ten years. V-Y and turndown flaps have been combined, with good results47. In a series of six patients who underwent postoperative isokinetic strength testing, deficiencies in peak torque plantar flexion were found to range from 2.5% to 22% compared with values for the unaffected limb. Mulier et al.48 reported on nineteen patients with a chronic Achilles tendon rupture involving a defect of >2 cm. Ten patients were treated with a gastrocnemius turndown flap (group 1), and nine patients were managed with a combination of a flexor hallucis longus transfer and a gastrocnemius turndown flap (group 2). At eighteen months, the outcomes were better in group 2. Subjective assessment showed that 40% of the patients in group 1 and 33% of those in group 2 had a decline in daily and sports activities. Objective assessment with isokinetic dynamometry at twelve months postoperatively demonstrated a 23% deficit in power and strength in group 1 compared with a 14% deficit in group 2. The range of ankle motion (compared with that on the contralateral side) was 70% in group 1 and 76% in group 2. The overall complication rate was high in this study, with seven of nineteen patients experiencing problems.
Peroneus Brevis Turco and Spinella26 augmented an end-to-end repair of the Achilles tendon with a modification of Pérez Teuffer's technique, by passing the tendon of the peroneus brevis through the distal stump rather than through the calcaneus. Excellent results were reported, but the outcome measures were not identified. Miskulin et al. also passed peroneus brevis through the distal Achilles tendon stump and used plantaris tendon as suture material50. In their series of five patients, all patients had an improvement in peak plantar flexion torque (range, 21% to 410%) and no complications were reported at one year after the operation. McClelland and Maffulli51 approached the Achilles tendon medially, and pulled the stump of the peroneus brevis through the inferior peroneal retinaculum, hence retaining its blood supply from the intermuscular septum. The tendon of the peroneus brevis was then woven through small coronal incisions in the distal stump of the Achilles tendon and again through similar incisions in the proximal stump. If the plantaris muscle was present, its tendon was used to augment the repair. Some investigators reported concerns that this technique could result in eversion weakness of the ankle13,27,52. However, the peroneus longus muscle has more than twice the eversion strength of the peroneus brevis. Theoretically, if the tendon of the peroneus brevis is placed distally in a lateral-to-medial direction, it does not duplicate the medial pull of an intact Achilles tendon27. However, the practical implications of these mechanical studies are unclear, and reconstruction with use of the tendon of the peroneus brevis has been reported to be functionally successful. Pintore et al.53 compared the results of treatment of acute ruptures with direct end-to-end anastomosis with the results of treatment of chronic ruptures with peroneus brevis transfer. At the time of follow-up, at a mean of fifty-three months, they found the patients who had had a chronic rupture to be satisfied with the result of the procedure despite experiencing a higher postoperative complication rate and greater loss of strength and calf circumference compared with their counterparts who had had an acute rupture.
Flexor Digitorum Longus
Flexor Hallucis Longus Advantages of flexor hallucis longus transfer include the tendon being long and durable and the muscle is stronger than that of other transfer candidates55, the axis of flexor hallucis longus contraction most closely resembles that of the Achilles tendon, and contraction of the flexor hallucis longus occurs in phase with the gastrocnemius-soleus complex. Its anatomical proximity makes the operative technique easier, without the need to open other compartments, and the muscle belly aids in the provision of a vascular supply to the distal stump of the Achilles tendon.
Gracilis
Fascia Lata Use of fascia lata to repair and augment a ruptured Achilles tendon has produced good results11,14,57. Bugg and Boyd58 reported the outcomes of repairs of twenty-one ruptures or lacerations, ten of which were chronic. They bridged the gap in the Achilles tendon with three strips of fascia lata and with a sheet of fascia lata sutured around these grafts in a tube-like fashion, with the serosal surface facing outward and the seam placed anteriorly and sutured to the proximal and distal stumps. A wire pullout suture was also used. No formal results were reported, but two case reports stated that the technique provided satisfactory function and cosmetic results at twelve months postoperatively.
Allografts More recently, Haraguchi et al.60 used Achilles tendon allografts to reconstruct both chronically ruptured Achilles tendons with a defect of >5 cm and Achilles tendons with extensive tendinopathy. In this procedure, cortical bone is removed from the patient's heel to allow room for the allograft, which is secured in position with two 4.0-mm screws. The graft is then placed under tension and repaired to the native Achilles tendon. No formal results were reported and the duration of follow-up was not mentioned, but neither rejection of the allograft nor transmission of disease to the host was observed.
Synthetic Grafts Parsons et al.62 used an absorbable carbon-fiber composite polymer in a series of forty-eight patients with a total of fifty-two Achilles tendon ruptures, twenty-seven of which were chronic. The polymer ribbon was woven through both the proximal and the distal stump of the tendon with six, seven, or eight passes to bridge the defect. A proximal tendon flap was used at the surgeon's discretion. According to the authors' own unvalidated scoring system, forty-five (87%) of fifty-two reconstructions yielded a good or excellent result at a minimum of one year. It was not stated how many ruptures were acute and how many were chronic. Complications included two reruptures, two deep infections, and three superficial infections. An investigation of the use of carbon fiber in sheep tendons showed carbon fiber fragmentation to be associated with poor collagen production63. With implantation of polyester fibers, the neotendon was more dense, had more collagen, and was more closely adherent63. Ozaki et al.64 used three layers of polypropylene mesh to treat neglected ruptures with gaps ranging between 5 and 12 cm in six patients. At the time of follow-up, at a minimum of 2.4 years, all patients showed satisfactory function and plantar flexion strength averaged 94% of that on the uninjured side. No complications were noted in the series. Dacron vascular grafts have been employed to augment repairs of Achilles tendon ruptures65,66 and have yielded good or excellent results when used for acute ruptures. Jennings and Sefton9 used polyester tape with a Bunnell-type suture in the treatment of sixteen chronic ruptures. The tape was tensioned so that the ankle could just dorsiflex to neutral. One patient required removal of the tape, one had a sural nerve injury, and three had superficial wound infection. No reruptures occurred during the mean follow-up period of three years.
Interposed Scar Tissue
Chronic Achilles Tendon Tears That Have Healed in Continuity
Minimally Invasive and Endoscopic Management In patients with a chronic rupture, the skin over the gap retracts over several weeks and remains retracted until the time of the operation. During surgery, this skin is incised and is then stretched in a relatively acute fashion to make space for the reconstructed tendon. Therefore, following the reconstruction, the skin over the gap may well be stretched so much that its vascular supply is impaired. Reconstruction techniques involve use of relatively long incisions and are prone to be complicated by wound breakdown. Some authors have incorporated skin-flap techniques to facilitate closure following reconstructive procedures for the Achilles tendon69. To avoid this problem in patients with a chronic rupture in whom a gap is palpable, we do not expose the tendon gap. Instead, we make a 5-cm longitudinal incision 2 cm proximal and just medial to the palpable end of the proximal stump. The second incision is 3 cm long and is also longitudinal but is 2 cm distal and lateral to the distal end of the tendon rupture. Care is taken to prevent damage to the sural nerve by making this incision as close as possible to the anterior aspect of the lateral border of the Achilles tendon. The distal stump of the Achilles tendon is then mobilized, freeing it of all of the peritendinous adhesions, particularly on the lateral side. This allows access to the lateral base of the distal tendon stump close to its insertion. The ruptured tendon end is then resected back to healthy tendon, and a number-1 Vicryl locking suture (polyglactin; Ethicon, Edinburgh, United Kingdom) is run along the free tendon edge to prevent separation of the bundles. The proximal tendon stump is then mobilized from the proximal wound, and adhesions are divided. Further soft-tissue release anterior to the gastrocnemius-soleus muscle allows maximal excursion, minimizing the gap between the two tendon stumps. A Vicryl locking suture is run along the free edge of the tendon to allow adequate exposure and to prevent separation of the bundles. To bridge the gap, we use the tendon of the peroneus brevis, which we harvest in a standard fashion51. The peroneus brevis muscle is then mobilized proximally to provide increased excursion. With use of a number-11 blade, a longitudinal tenotomy parallel to the tendon fibers is made through both stumps of the tendon. An artery clip is used to develop the plane, from lateral to medial, in the distal Achilles tendon stump, and the peroneus brevis graft is passed through the tenotomy site. With the ankle in plantar flexion, a number-1 Vicryl suture is used to suture the peroneus brevis to both sides of the distal stump. The tendon of the peroneus brevis is then passed beneath the intact skin bridge into the proximal incision and is passed from medial to lateral through a transverse tenotomy in the proximal stump and is further secured with a number-1 Vicryl suture. Finally, the tendon of the peroneus brevis is sutured back onto itself on the lateral side of the proximal incision (Figs. 6-A, 6-B, and 6-C).
Recently, Lui70 described a technique for endoscopic assisted transfer of the tendon of the flexor hallucis longus to minimize soft-tissue dissection in the treatment of chronic Achilles tendon tears. The procedure is performed with use of very small incisions (<1.5 cm each), but it is unclear whether the continuity of the Achilles tendon is adequately restored and functional recovery would have to rely solely on the flexor hallucis longus. Nevertheless, the technique is minimally invasive and minimizes injury to the soft tissues. Three cases of chronic Achilles rupture were described. At a mean of fifteen months postoperatively, none of the patients walked with a limp.
We are not aware of any studies focusing specifically on postoperative management following operative treatment of chronic Achilles tendon ruptures. However, the present trend is for early mobilization after the operative repair of acute ruptures71. Recent meta-analyses have shown that early functional treatment protocols, when compared with postoperative immobilization, led to more excellent subjective responses and no difference in the rerupture rate72. We use the same protocol for chronic ruptures: the patient wears a below-the-knee cast for two weeks and is encouraged to bear as much weight as possible on the operatively treated limb as soon as possible71. At two weeks, the cast is removed and a lower leg anterior splint is applied, allowing the ankle to be plantar flexed fully but not dorsiflexed and allowing inversion and eversion. These exercises are performed against manual resistance. At six weeks, the anterior splint is removed, and the patient gradually returns to his or her normal activities. Recovery can take as long as nine to twelve months.
Tissue engineering may prove useful for managing tendon ruptures in the future. In one study, 1-cm-long rabbit Achilles tendon defects were core bridged with a polydioxanone suture and then encapsulated in human amnion extracellular matrix seeded with third-passage fetal skin fibroblasts73. There were two control groups. In control group I, defective tendons were core bridged with a polydioxanone suture and encapsulated with human amnion extracellular matrix without fibroblasts. In control group II, the defects were only core bridged with polydioxanone suture. Gross examination, light microscopy, immunohistochemical examination, scanning electron microscopy, and biomechanical measurement of the repaired tendons were performed at one, two, and three months postoperatively. The optimal cell concentration for seeding fibroblasts was 3.5 x 106 cells/mL. Cells grew well on the extracellular matrix. Immunohistochemistry showed that the labeled seed fibroblasts played an important role in tendonization. The rate and quality of healing in the experimental group were superior to those in both control groups. The values for the structural and material properties of the implants that had received human amnion extracellular matrix seeded with third-passage fetal skin fibroblasts typically were approximately twice those of the controls, and the repaired tendons were larger in cross section and better organized histologically than the repairs performed with suture alone. The tensile strength in the experimental group was the greatest, at 81.8% of normal after three months. The authors concluded that human amnion extracellular matrix seeded with third-passage fetal skin fibroblasts promotes rapid repair of a tendon defect. In another study, polyglycolic acid scaffolds seeded with tenocytes were implanted into hen flexor tendon defects74. Twelve weeks after the operation, the tenocytes and collagen fibers became longitudinally aligned. At fourteen weeks, the tissue-engineered tendons displayed a typical tendon structure with a breaking strength of 83% of normal. A potential application of mesenchymal stem cells is ex vivo, de novo tissue engineering. This technique involves construction of whole body tissues in the laboratory and their subsequent implantation into patients. Such tissue-engineered tendons potentially could be used to bridge large areas of tissue loss. Tissue engineering is an emerging field, and many difficulties need to be overcome before this approach becomes a real option in the management of tendon disorders. For example, effective vascularization and innervation of implanted tissue-engineered constructs must take place. Vascularization is important for the viability of the construct. Innervation is required for proprioception and to maintain reflexes that are mediated by Golgi tendon organs to protect tendons from excessive forces75.
Chronic Achilles tendon ruptures are uncommon but potentially debilitating. The choice of management is partly guided by the type of tendon lesion76, with most injuries requiring operative management77. Many techniques can be used to repair or reconstruct a tendon with a chronic rupture. It is difficult to compare different techniques. Most studies have been retrospective and small and have focused on the results of a single technique (Table I). Functional outcome measures have also been diverse, given the highly variable outcome criteria that have been applied. Tissue engineering shows promise, but additional research and clinical trials are needed to evaluate its efficacy in humans. 
NOTE: The authors thank Dr. Paola Casillo for the help with the illustrations.
  CiteULike  Connotea  Del.icio.us  Facebook  Technorati  Twitter What's this?
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Top
Abstract
Introduction
| home | CME | help | feedback | subscriptions | archive | site index |
|
Stanford University Libraries' HighWire Press (TM) assists in the publication of JBJS Online. |